First Report of Fusarium verticillioides Causing Fusariosis on Triticale Grain in Serbia

Triticale (Triticosecale Wittmack) is a cereal crop species developed to combine positive traits of wheat and rye into a single plant (Arendt and Zannini, 2013). Due to its high protein content, favourable amino acid composition and nutritional values higher than maize, triticale is an excellent component for preparing feed for domestic animals (Đekić et al. 2019). In May 2017, discoloured spikes of triticale were observed in a field in Zemun Polje, Serbia, with a disease incidence between 15 and 20%. A total of 400 kernels obtained from discoloured spikes were surface sterilised with 1% sodium hypochlorite solution for 3 minutes and then rinsed 3 times with sterilized water and plated on potato dextrose agar (PDA) at 25°C incubated in the dark for 7 days. A total of 15 isolates of genus Fusarium on PDA formed cottony white to greyish purple colony with dark yellow to purple grey reverse and average colony. Obtained isolates were transferred to carnation leaf agar (CLA) and synthetic nutrition agar (SNA), for 7-day incubation in the dark at 25°C. Ten isolates formed “rabbit ear” monophialides which is the main characteristic of Fusarium verticillioides (Sacc.) Nirenberg. Microconidia are formed from monophialids in long chains. Their shape is oval with a flattened base, without septa (4.0-18.0 x 1.5-4.5 µm). Shape of macroconidia is slightly falcate to almost straight, (3.5-4.5 x 31-58 µm). Chlamydospores are not produced (Leslie and Summerell, 2006). The genomic DNA from one F. verticillioides isolate was extracted using the DNeasy Plant Mini kit (Qiagen, Hilden) according to the manufacturer’s protocol. Molecular identification was confirmed by sequencing the internal transcribed spacer (ITS), translation elongation factor-1 alpha (EF-1α) and RPB2 (O′Donell, 2000). Sequence was deposited in GenBank as MZ664391, MZ666958 and MZ666957. This sequence was compared with the sequences of F. verticillioides strains registered in the GenBank database based on nucleotide similarity. It showed 100% identity to the sequences MT180471.1 (ITS), MN861767.1 (EF-1 α) and MT264836.1 (RPB2). Pathogenicity of all isolates was tested on 20 randomly selected triticale spikes in four replicates (Mesterházy et al. 1999). Inoculation was performed when half of the plants reached the flowering stage, by spraying with 20 ml of spore suspension (1 × 106 spores/ml from 7-day-old cultures on PDA). F. verticillioides RBG 1603 Q27 was used as a positive control. Inoculated spikes were covered with PVC bags for 48h. Discoloured spikes were observed after 3 week incubation in a greenhouse at 20°C with a 16h light/8h dark photoperiod. All inoculated spikes showed symptoms, similar to those from field infections. Control spikes were symptomless. The fungus was reisolated and was morphologically identical to the original isolates, thus completing Koch’s postulates. Based on morphological, molecular and pathogenic features the isolated fungus was identified as F. verticillioides. Fusarium species infect crop plants worldwide resulting in yield loss and reduced grain quality due to mycotoxin contamination (Asam et al, 2017). In Serbia F. verticillioides was isolated from wheat and barley grains (Stanković et al., 2012) and to the best of our knowledge, this is the first report of F. verticillioides on triticale grain in Serbia.

Effects of intercropping on temperate grasses canopy architecture and nutritive profile

This paper aimed to evaluate the impact of intercropping between oats and triticale species, over three defoliation cycles. The experiment occurred in two winters in a row, and was in split-plot randomized complete blocks design (20 plots) with five species combination, four blocks and three defoliations. The main plots were the species combination: black oat (Avena strigosa cv. IAPAR 61) – BO, white oat (Avena sativa cv. IPR Emerald) – WO, triticale (X Triticosecale Wittmack cv. Tpolo 981) – T; and the intercropping: black oat + triticale – BOT, and white oat + triticale - WOT. The sub-plots were the three defoliations cycles initially scheduled to be every 28 days. The intercropping between oats and triticale did not affect the accumulated dry matter yield (DM), but it also improved the pastures, as an increase on crude protein content (CP) (about 1.85% greater in WOT than WO; and 2.7% greater in BOT than BO). The number of leaves was also increased by the intercropping, from 4.2 (WO) and 3.7 (BO) to 7.6 (WOT) and 7.2 (BOT) leaves per main stem. Over the defoliation cycles, the maximum average of growth rate (2.72 t DM ha-1 ºCd-1), tiller per plant (10 tillers plant-1) and main tiller height (53.2 cm) were unanimously observed at third defoliation. The changes observed did not reduced the nutritional quality of the pastures, therefore both are highly indicated to these conditions.

Evaluation of triticale variety samples by crop structure elements

Breeding improvement of triticale requires the search for genetic sources for hybridization. Our research aims at identifying high-yielding genotypes of winter triticale and determining the influence of structural elements on this indicator to optimizing selection during the breeding process. In 2014–2018, fifty variety samples of triticale were studied in the North Caucasus Federal Agricultural Research Centre. Soil – ordinary chernozem, medium loamy, medium-thick, low-humus. Black fallow preceded all × Triticosecale Wittmack samples. The experiment was laid having only one replication. The area of the plot was 1 m2. Triticale variety ‘Valentin 90’ served as a standard. We identified 25 medium-yielding and 25 high-yielding varieties. Grain yield in the first group was lower than in the second one and amounted to 784 ± 191 g/m2 and 1024 ± 202 g/m2, respectively. High-yielding samples exceeded the average-yielding ones in the number of spikelets (32.0 ± 2.17 and 31.2 ± 2.18 pieces), grains per ear (69.1 ± 13.0 and 64.5 ± 10.6 pieces) and weight of grain per ear (3.26 ± 0.61 and 3.00 ± 0.61 g). The yield and weight of grain per ear vary significantly (Cv > 20 %). Ear size, number of grains in the ear and spikelet, 1000 grain weight and triticale ear density do not vary much (Cv > 10 %). The most stable trait is the number of spikelets per ear (Cv < 10 %). A weak positive correlation was observed between the yield and number of grains per spikelet (r = 0.18 ± 0.06), yield and ear (r = 0.22 ± 0.06), as well as yield and weight of grain per ear (r = 0.29 ± 0.06). In the group of high-yielding variety samples, there was a reliable weak negative correlation between the yield and number of spikelets per ear (r = −0.32 ± 0.08), between the yield and ear density (r = −0.24 ± 0.09). Grain yield of more than 1.000 g/m2 had the following variety samples – ‘Ugo’, ‘RAH 121/04’, ‘Kitaro’, ‘Tewo’, ‘Ratne’, ‘Slavetne’, ‘Adas’, ‘Dar Belorussii’, ‘Dinamo’, ‘Dinaro’, ‘Liniya 71’, ‘Lamberto’, ‘PRAG 203/1’, ‘Nemchinovsky 1’ and ‘Valentin 90’ (standard).

Identification and Fine-Mapping of Quantitative Trait Loci Controlling Plant Height in Central European Winter Triticale (×Triticosecale Wittmack)

The quantitatively inherited trait plant height is routinely evaluated in triticale breeding programs as it substantially influences lodging and disease susceptibility, is a main contributor to biomass yield, and is required to improve hybrid seed production by fine-tuning plant height in the female and male parental pools in hybrid breeding programs. In this study, we evaluated a panel of 846 diverse Central European triticale genotypes to dissect the genetic architecture underlying plant height by genome-wide association mapping. This revealed three medium- to large-effect QTL on chromosomes 5A, 4B, and 5R. Genetic and physical fine-mapping of the putative QTL revealed that the QTL on chromosome 5R most likely corresponds to Ddw1 and that the QTL on chromosome 5A is likely to be Rht12. Furthermore, we observed a temporal trend in registered cultivars with a decreasing plant height during the past decades, accompanied by an increasing use of the height-reducing alleles at the identified QTL. In summary, our results shed new light on the genetic control of plant height in triticale and open new avenues for future improvement by breeding.

Utilisation of triticale (X Triticosecale Wittmack) and residual oat flour in breadmaking

During the last few years, non-bread cereals, as a rich source of bioactive components, play an increasingly important role in the production of new healthier food. A large number of diet-related diseases in society requires developing and regular consumption of high-quality food. In this study, triticale flour was supplemented with residual oat flour (ROF), which is a by-product in the production of oat fibre concentrate, to obtain triticale-oat bread with improved chemical composition and quality. The flours obtained from 3 winter triticale cultivars were enriched with 10%, 15%, and 20% of ROF. An increasing level of ROF resulted in higher protein and lipids content and a two-fold increase in β-glucan content (from 0.3% for control breads to 0.6% for 20% ROF) what improved the quality of dietary fibre in breads (DF). The bread parameters, especially bread volume (BV), the shape of loaves, crust colour and crumb texture, decreased with the addition of ROF. The triticale-oat breads with the best quality were obtained from 10% addition of ROF. Results confirmed the possibility of utilisation triticale and ROF for the production of bread with a unique chemical composition constituting a simultaneously rich source of DF.

Nanopartículas de quitosano mejoran la calidad nutracéutica de germinados de triticale

El uso de nanopartículas de quitosán (NPs CS) se ha vuelto una alternativa prometedora en la agricultura moderna como un inductor en la biosíntesis de metabolitos secundarios. El objetivo del presente trabajo fue evaluar el efecto de NPs CS en la calidad nutraceútica de germinados de triticale (x Triticosecale Wittmack). Dosis creciente de NPs CS: 0, 0.1, 0.2, 0.4 y 0.8 mg ml-1 se aplicaron una sola vez en la etapa de imbibición, después se dejaron en cajas Petri durante 7 días a 25 ±2 °C de temperatura. Las NPs CS no afectaron la germinación ni el peso freso de la raíz a las concentraciones probadas, y a la concentración de 0.1 mg ml-1 aumentó el peso fresco del brote hasta 83.3%. En presencia de 0.8 mg ml-1 de las NPs CS los compuestos fenólicos disminuyen un 7% y aumentan 29% los flavonoides. Los resultados confirman un efecto promotor de las NPS CS en los germinados, abriendo la posibilidad de ser utilizadas como inductores en la biosíntesis de compuestos bioactivos en germinados de triticale.

Quantitative Trait Loci (QTL) Associated With Leaf Development in Winter Triticale (× Triticosecale Wittmack) Seedlings

The vitality and the development in the seedling stage is crucial in winter cereal’s life cycle, especially before and during winter. It has been reported that rapid seedling establishment and early growth may lead to higher crop yield. Localization of cereal genome regions is not often analysed in the seedling stage. The aim of this study was to identify winter triticale genome regions (QTL) associated with seedling leaves development. Based on ‘Hewo’ x ‘Magnat’ DH lines population genetic map composed of 3539 molecular markers assigned to 20 linkage groups with 4997.4 cM map length, in total 40 loci were identified by a composite interval mapping (CIM). Among them, 22 loci appeared in at least two experiments, were common for all analyzed traits as well as were identified on wheat chromosome 4B and on rye chromosomes 1R, 4R, 5R and 6R. Those loci explained up to 21.7% of phenotypic variation (Qwsl.hm.4R.2) and had LOD value up to 31.1 (Qlsl.hm.5R.1). The results of QTLs of seedling leaves development could be successively associated with QTLs of the freezing and fungal infection seedlings tolerance identified in this mapping population.